Effects on asthma and induction of interleukin-8 caused by Asian dust particles collected in western Japan.

OBJECTIVE: Asian dust storms (ADS) contain various airborne particles that may augment airway inflammation by increasing the level of interleukin-8. The objective of the study was to investigate the association of exposure to an ADS with worsening of symptoms of adult asthma and the effect of ADS particles on interleukin-8 transcriptional activity. METHODS: The subjects were 112 patients with mild to moderate asthma who recorded scores for their daily upper and lower respiratory tract symptoms and measured morning peak expiratory flow (PEF) from March to May 2011. Interleukin-8 transcriptional activity was assessed in THP-G8 cells that were exposed to airborne particles collected during days of ADS exposure. RESULTS: Of the 112 patients, 31 had comorbid allergic rhinitis (AR) and/or chronic sinusitis (CS), and had worsened scores for upper respiratory tract symptoms on ADS days compared to non-ADS days. Scores for lower respiratory tract symptoms during ADS days were higher than non-ADS days in all patients. Three patients also had unscheduled hospital visits for exacerbation of asthma on ADS days. However, there was no significant difference in daily morning PEF between ADS and non-ADS days. Airborne particles collected on ADS days induced interleukin-8 transcriptional activity in THP-G8 cells compared to the original soil of the ADS. CONCLUSION: Exposure to an ADS aggravates upper and lower tract respiratory symptoms in patients with adult asthma. ADS airborne particles may increase airway inflammation through enhancement of interleukin-8 transcriptional activity.

Pollen augments the influence of desert dust on symptoms of adult asthma patients.

BACKGROUND: East Asian desert dust storms that occur during mainly spring are called Asian dust storms (ADS). Our objective was to study the association of pollen and ADS with symptoms of adult asthma patients in Japan. METHODS: We designed a telephone survey to investigate the upper and lower respiratory, ocular, and skin symptoms of asthma patients during ADS in February, March, and December on 2009. Peak expiratory flow (PEF) was also measured from February to May. RESULTS: We surveyed 106 patients in February, 101 patients in March, and 103 patients in December. In February and March, Japanese cedar and/or cypress pollen was also in the atmosphere during ADS, but no pollen was identified during December survey. Worsening of upper or lower respiratory, ocular, or skin symptoms was noted by 20.8% of patients in February, 33.7% in March, and 16.5% in December. Worsening of symptoms was significantly more common in March than in February or December. Two patients needed emergency treatment for exacerbation during ADS in March, but no patient needed hospitalization in any period. There was no significant difference of the daily morning PEF/personal best PEF ratio between ADS days and control days. However, in patients with worsening of upper and/or lower respiratory tract symptoms, the daily morning PEF/personal best ratio was significantly associated with the atmospheric level of particulate matter, but not with levels of pollen or other air pollutants. CONCLUSIONS: Pollen augmented symptoms in adult asthma patients, but ADS on its own also were able to aggravate symptoms and pulmonary function.

Difference in interleukin-8 transcriptional activity induced in THP-G8 cells by particulate matter collected in winter and summer in western Japan.

BACKGROUND: Airborne particulate matter (PM) may stimulate production of pro-inflammatory cytokines, and thus exposure to PM affects pulmonary diseases. However, the effects of PM on pulmonary diseases have differed among studies. METHODS: PM was collected from February 2 to 28 (winter) and June 1 to 17 (summer) in 2013 in Yurihama, Japan, using filters to separate particles with different aerodynamic diameters (1.1 to <2.2 µm, 2.2 to <3.3 µm, 3.3 to <7.0 µm, and 7.0 to <10 µm). Interleukin (IL)-8 transcriptional activity in THP-G8 cells was examined in response to winter and summer PM with different diameters. RESULTS: IL-8 transcriptional activity induced by winter PM was significantly higher than that with summer PM for each diameter. For winter PM, IL-8 activity increased with an increased diameter, whereas this activity did not differ between a solvent control and each summer PM diameter. This indicates that summer PM does not stimulate production of IL-8 in THP-G8 cells. CONCLUSION: The effects of PM on production of pro-inflammatory cytokines differ with the season and PM diameter. This suggests that the compositions of PM differ on season, and the evaluation of compositions of PM is important in understanding the association of health with short-term exposure to PM.

Influence of Asian Desert Dust on Lower Respiratory Tract Symptoms in Patients with Asthma over 4 Years.

The Asian Dust Storm (ADS) aggravates symptoms and pulmonary dysfunction in adult asthma patients. Our objective was to investigate the association of air pollutants and metals in desert dust with worsening of asthma symptoms during the ADS. A telephone survey was performed to investigate the upper and lower respiratory tract symptoms, ocular symptoms and skin symptoms of asthma patients during the ADS in March between 2007 and 2010. Four surveys were conducted in 46 patients. Two patients noted worsening of lower respiratory tract symptoms in all four surveys, as well as 2 patients in three surveys, 7 patients in two surveys, and 9 patients in one survey. There was no worsening of lower respiratory tract symptoms in 26 patients. In each patient, the influence of the ADS on lower respiratory tract symptoms varied between surveys. In 2010, the level of suspended particulate matter was highest in all four years, but the smallest number of patients noted worsening of lower respiratory tract symptoms. Among pollutants, only the maximum concentration of nitrogen dioxide during the ADS was significantly associated with the worsening of lower respiratory tract symptoms. The influence of the ADS on lower respiratory tract symptoms of adult asthma patients is variable.